Home
 
  Home     News     Products     Contact Us     Links    
 
 
Products
 

Information

Agency Products

COPPER PRODUCTS - HOW DO THEY WORK?


 

1. Particle Sizing:

The smaller the particle size, the better the coverage on the plant surface. This is illustrated on the diagram below:

Coppox® has an average particle size of 1.58 microns. This has a direct effect on coverage, tenacity of the product and ultimate fungicidal activity.

 



2. Copper Content:

This is important, as copper is the active ingredient.

Copper products have a range of copper contents, the majority are in the 15% to 50% active copper range.

Coppox® contains 500g/kg active copper (or 50% active).

This provides the user with excellent value for money in comparison to those products on the market containing far less active ingredient.




3. Cupric Chloride Levels:

Cupric Chloride is found in all copper products, and – when present in large levels - is responsible for the burning sometimes associated with such products.

The cupric chloride levels of Coppox® ranges between 8-25ppm, which has distinct benefits to crop safety




4. Heavy Metal Impurities:

There are a number of heavy metals associated with copper products. These metals occur together in their natural state.

Coppox® does not contain detectable levels of cadmium, mercury or arsenic, and has an average of 52ppm Lead (the legal limit being 250ppm).

We have tested some different products available on the market, and have turned up some interesting results. In once traded product, the lead level was 25 times over the legal limit – set by the World Health Organisation




5. Hydroxides vs. Oxychlorides

The manufacturing process for both hydroxides and oxychlorides is exactly the same, to a point. This point is the final stage - where cupric hydroxide continues for one more step:

Copper Products

In the case of hydroxides, this additional step results in additional cost. Hence, hydroxides will always be more expensive on a cost-per-hectare basis than oxychlorides




6. Copper Wire:

The quality of the copper wire used from the onset will determine the heavy metal impurities in the final product.

There is a very wide range of quality for scrap for all metals – from impure to high grade wire at 99.9%. Copper scrap will always be used in the production of copper products, as pure copper (copper cathode) is not commercially possible.

Coppox® is manufactured only from 99.9% pure wire, resulting in a consistent, high-quality product.

Unfortunately, not all copper products are manufactured from such high quality material. This results in a product with any number of heavy metal impurities.

We encourage all growers to request specifications of any copper products they purchase, to ensure they are receiving a good quality product.

The legal limit for lead in Australia is 250ppm – we have tested some traded products at 6,000ppm!

Bear in mind these products coat the fruit and vegetables we consume, and high levels of lead (and some other metals) are an environmental hazard.



7. The Manufacturing Process:

Copper wire is reacted with hydrochloric acid. The reaction time determines the amount of copper chloride in the end product. The cupric chloride (impurity) is the “burning culprit” in copper-containing products, and an undesirable element.

Efficiency in production is measured by output. The more product, the greater the volume and the efficiencies. The quicker the reaction time, the greater the volume..

The desire to maximise volume resulted in high cupric chloride levels, and consequently greater amounts of crop damage. This then led to the perception that (all) copper oxychlorides “burn.”

Melpat Coppox® now has cupric chloride/copper chloride levels down to between 8 – 25ppm! For this reason we will be working towards registering crops such as tomatoes and mangoes during flowering – a very sensitive stage in the plant’s growth.

Once again, copper chloride levels can be found on the product specifications, which can be requested from the manufacturer.



8. Soluble vs. Insoluble Copper Products:

The fungicidal / bacterial properties of copper products are based on copper (the active ingredient) being slowly dissolved in moisture (rain or irrigation) on the plant leaf - in the presence of weak organic acids.

As plant infections take place, small amounts of copper are released on the plant surface to kill or inhibit germination of micro-organisms.

I.e, the mode of action of all copper fungicides is by interfering with the enzyme system of spores and mycelium, a process that is usually irreversible. If forms a chemical barrier against attack.

Copper never controls plant disease when absorbed into the plant. Soluble liquid copper products have very high and quick absorption by the plant, and therefore are not as effective as insoluble copper products.

To summarise: Coppox (and other insoluble copper fungicides) form a chemical barrier that protects the plant tissue from fungal attack. It does not have any system fungicidal value.


 
IC 2016